At present, the amount of information being transmitted through internet and high-speed data exchanges between servers is at a high level and growing rapidly. The information-technology (IT) industry is already encountering the physical limits of current electrical components, interconnections and assembly technologies.
In making their invention, the inventors have recognized that optical devices could offer high speed data communication because the data signals stay within the optical layer throughout the entire routing path, without the need for expensive and complicated electrical-optical interfaces. However, that would require building complex optical communication systems with large numbers of opto-electronic devices and high degrees of functionality.
Currently, some of the most effective opto-electronic devices are constructed on substrates that cannot be used to construct the entire optical system, either because of prohibitive costs, and/or because such substrates are not large enough to support the entire optical system. As one work-around to this problem, some have used less effective opto-electronic devices because they could be readily incorporated on the substrates used for large-scale optical systems. However, this approach has the disadvantage of being constrained to using less effective opto-electronic devices. As another work-around, others have resorted to methods that first individually make the opto-electronic devices on individual mini-substrates (usually formed on a common substrate that is later diced into several mini-substrates), followed by attaching the mini-substrates to the main substrate of the optical system, and thereafter forming the optical waveguide structures of the optical system around the mini-substrates. However, this approach is expensive, is prone to misalignment of the optical core layers, usually requires precision polishing of the mini-substrates (to reduce their thicknesses), and constrains the processing temperatures for making the optical system to the highest temperature that the finished mini-substrate can withstand. Misalignment of optical components causes significant attenuation of the light signal. The possibility of misalignment must be considered when designing an optical system, and this consideration usually constrains the size and/or functionality of the optical system.
The present invention is made with a view to overcoming these disadvantages.